4 Replies Latest reply: Sep 23, 2013 1:22 PM by Prokat99
tcpeders Level 1 Level 1

In the morning when I go to turn on the computer the tower will light up and I hear the harddrive start up. However, the monitor doesn't turn on at all. If I unplug the monitor from the power source and the tower, plug it back in, and restart it will usually start working again after two or three tries. It's quite a hassel to have to unplug everything and plug it back in so many times...


It is a mac pro from 2010 with an apple LED monitor.

Mac Pro, iOS 6.1
  • The hatter Level 9 Level 9

    your UPS is too small and you do want one, or you are straiining your circuit? is that possible? sounds like trying to draw more than available. Any nearby portable heaters or anything else?

  • Jonathan Hodges Level 1 Level 1

    Running into the same issue. mid-2010 Mac (Mac5,1) with 16GB of RAM, 12 cores and running two monitors (an Eizo and an old 20-inch Apple cine). Six identical setups. I'm only having the black monitor issue on the two running Lion and Mountain Lion. The four Snow Leopards are still running fine.


    I thought it might be an incompatibility issue between Lion and Mountain Lion and the Radeon HD 5870 graphics card, but I dumped an old NVIDIA GeForce GT 120 card in one of the boxes and ran into the same issue (also, the fans started going crazy).

  • Grant Bennet-Alder Level 9 Level 9

    What graphics card? What Interface, DVI? Under 1920 wide? any adapters?

  • Prokat99 Level 1 Level 1

    I am having the same issue on a 2008 8 core, with ATi 2600xt and two monitors.  It is extremely annoying as it is a crap shoot everytime I turn on the computer.  For some reason, 10.8.5 has tremendously increased the odds of this happening.  It used to be once a week maybe, now, it is 9 out of 10 times, which starts my work day off in a ****** way. 

    Anyone come up with a fix?  I can see this is an old thread, but no answers are posted.